The present invention relates in general to gas switches for selectively providing a gas exchange between at least two defined regions and, in particular, to a gas switch for use in an air cell battery.
U.S. Pat. No. 3,897,265 discloses a conventional air cell battery or gas depolarized electrochemical cell. The air cell battery disclosed is of the type known as a zinc air button cell. Conventionally, this type of button cell uses an active material such as amalgamated zinc and a cathode material such as carbon black with a catalyst and a hydrophobic binder dispersed throughout the cathode. In operation, when electricity is drawn from the battery, oxygen within the battery is used up by the cathode material and new oxygen is admitted into the battery through openings in the housing of the battery. A serious disadvantage of these batteries is that because of the opening in the housing the battery may lose or gain water depending upon the humidity content of the air surrounding the battery. Such gain or loss of water from the battery is detrimental to the operation of the battery. Typically normal changes in humidity seriously shorten the usable length of the battery.